CO2

Carbon Dioxide (CO2)

Carbon dioxide (CO2) is a colorless, odorless gas that is vital to life on Earth. It is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. Carbon dioxide is a trace gas in Earth's atmosphere, currently constituting about 0.04% (400 parts per million) of the atmosphere.

Chemical Properties

CO2 is a linear molecule with a bond angle of 180 degrees. It is non-polar and has a molar mass of 44.01 g/mol. The gas is soluble in water, forming carbonic acid (H2CO3), which is a weak acid. This reaction is reversible and plays a significant role in the carbon cycle.

Biological Role

Carbon dioxide is a critical component of the photosynthesis process, where plants, algae, and cyanobacteria convert CO2 and water into glucose and oxygen using sunlight. This process is essential for the production of organic matter and oxygen, supporting life on Earth.

In animals, CO2 is a byproduct of cellular respiration, where glucose and oxygen are metabolized to produce energy, carbon dioxide, and water. The CO2 is then transported in the blood to the lungs, where it is exhaled.

Environmental Impact

CO2 is a significant greenhouse gas, contributing to the greenhouse effect and global warming. Human activities, such as the burning of fossil fuels and deforestation, have increased atmospheric CO2 levels, leading to climate change.

Industrial Uses

Carbon dioxide is used in various industrial applications, including:

• As a refrigerant in its liquid form.
• In the production of carbonated beverages.
• As a fire extinguisher due to its ability to displace oxygen.
• In enhanced oil recovery techniques.

Medical Relevance

In medicine, CO2 is used in laparoscopy to insufflate the abdomen, providing a clear view for surgeons. It is also used in respiratory therapy to stimulate breathing in patients with respiratory failure.

Safety and Handling

While CO2 is non-toxic, high concentrations can displace oxygen in the air, leading to asphyxiation. Proper ventilation is essential when handling CO2 in enclosed spaces.

See Also

• Carbon cycle
• Greenhouse gas
• Photosynthesis
• Cellular respiration